Plastic weld pourer component

ABSTRACT

A plastic weld pourer component for connecting to a plastics container part, more particularly a container part of film-like plastics material, comprises at least one welding rib extending circumferentially about a neck portion defining a discharge passage, and having a welding edge or face. The welding edge is provided at a welding flash formed on a rib base portion of the welding rib having a smaller dimension in directions perpendicular to the circumferential direction than that of the rib base portion.

The invention relates to a weld pourer component of a plastics materialfor welding to a plastics container part and more particularly to a weldcomponent for connecting to a container part in the form of a refill bagmade of a film-like plastics material for the storage of e.g. liquid orpasty detergents.

BACKGROUND

Since a weld pourer component is a dimensionally stable plasticsmolding, difficulties may be experienced in welding together thedifferent plastics materials due to the elasticity of the film materialof the container part, since the film material tends to tear off alongthe welding zone due to overheating and the like. This is why it isprincipally desirable, for reasons of good heat transport or in avoidingoverheating, to form welding ribs on the weld component as thin-walledas possible. Thin-walled welding ribs may, however, createnotch-sensitive welding zones in the film material. It has already beenproposed to perform welding ahead a background wall of the weldcomponent so that the film material during welding is able to come intocontact with and be supported by the background wall. The disadvantageof this measure is the detrimented removal of heat from the welding zoneand thus the danger of the film material being overheated.

SUMMARY OF THE INVENTION

The object of the invention is to provide a plastic weld pourercomponent of the type mentioned above which permits cost-effectivemanufacture and may be processed without problems. More particularly,the object of the invention is to prevent tearing off of the filmmaterial during welding and in subsequent use.

For achieving this object the weld pourer component according to thepresent invention for welding to a plastics container part made offilm-like plastics material, comprises at least one welding ribextending circumferentially of a neck portion defining a dischargepassage and having a welding edge provided on a welding flash integrallyformed on a rib base portion of the welding rib and having a smallerdimension in directions perpendicular to the circumferential directionthan that of the rib base portion.

Accordingly, each welding rib comprises a relatively thick-walled ribbase portion which may have a rounded peripheral surface to which anarrow thin-walled welding web or flash is integrally formed, the outercircumferential edge of which forms a welding edge or face. Due to thethin-walled configuration of the welding flash the temperatures of thefilm during welding can be readily maintained at such a level thatoverheating of the film material is effectively avoided.

A firm weld connection is attained since the welding can be controlledso that the welding flash is melted down during welding to such a degreethat it practically disappears, thereby permitting a supporting contactof the film material with the rounded relatively wide outercircumferential surface of the rib base portion. As a result the forcesoccuring during welding and in later use between the weld component andthe film bag can be transmitted at the welding zone free of any notcheffects to a substantial degree. Thus by surprisingly simple means aneffective measure in preventing tearing of the film material is achievedby the invention. Since the rib base portion of the weld component isnot involved in the welding operation, or only in an indirect manner, itcan be optimized as regards a good heat transport from the welding zonewhich is a further effective means in preventing the formation of cracksin the region of the welding zone. More particularly, each welding ribmay be provided with a large heat-transporting surface like a coolingfin. A thin-walled partition may be provided between adjacent weldingribs for increasing stability, which fixes the radial and axialpositions of the welding ribs with respect to each other. Further theweld pourer component in accordance with the invention may be dividedalong an axial plane, more particularly in the axial center plane, inwhich each separate portion comprises a discharge passage. Each separateportion may be welded to a separate container part and the two separateportions may then be joined to each other so that an outer configurationresults corresponding to that of a one-part weld pourer component inaccordance with the invention.

The invention will now be explained in more detail with reference to anembodiment and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a weld pourer component formed in accordance with theinvention in an overall view (left-hand half) and in a longitudinalsection view (right-hand half),

FIG. 2 shows the weld pourer component in a similar represention as thatof FIG. 1 but in a side view,

FIG. 3 shows the weld pourer component according to FIG. 1 as viewedfrom above,

FIG. 4 shows a weld pourer component in accordance with anotherembodiment of the invention as viewed from above,

FIG. 5 shows the weld pourer component according to FIG. 4 in a partlysectioned side view, and

FIG. 6 shows the weld pourer component according to FIG. 4 as viewedfrom underneath.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The weld pourer component in accordance with a preferred embodiment ofthe invention is an integrally formed part made of a dimensionallystable plastics material, such as polyethylene or polypropylene, whichcan be inserted in a slot-like opening of a prefabricated container part(not shown) and can be connected thereto permanently by welding, e.g.ultrasonic welding. More particularly, the container part may be made ofa film-like plastics material, as is being used more and more for refillbags for storing e.g. liquid or pasty detergents, in minimizing waste.Although the permanent connection between the weld pourer component andcontainer part is generally done by welding, it may also be produced byother methods of heat transport such as hot sealing or by adhesivebonding. It will be appreciated that the invention is restricted neitherto the plastics materials nor the application as above-mentioned, itinstead also permitting use in other applications with similaradvantages, where it is desired to connect a flexible plastics materialsubstantially along a line to a dimensionally stable plastics material.

The weld pourer component comprises pursuant to FIGS. 1 to 3, which showa first embodiment of the invention, a substantially tubular neckportion 1 having a suitable axial extension through which athrough-passage 3 extends axially. The through-passage 3 provides acommunication between the interior of a container part (not shown) andthe environment when the weld pourer component is connected to thecontainer part.

On an outer circumferential portion of the neck portion 1 near an axialend thereof a thread 2 may be formed on which a screw closure cap (notshown) may be screwed to close off the through-passage 3. Instead of ascrew thread 2 a clamping collar could be provided on the neck portion 1to secure in a positive manner a closure cap to the weld pourercomponent by press action.

Along a portion of the neck portion 1 near its other axial end one ormore, in the case of the present embodiment four, welding ribs 4 areformed parallel to each other in axial spacing. Each welding rib 4 islocated in a radial plane relative to the longitudinal center line ofthe weld pourer component and comprises a relatively thick-walled ribbase portion 6 as well as a welding flash 7 formed on the outercircumferential surface or rim of the rib base portion. The weldingflash 7 is also located in the radial plane of the thick-walled rib baseportion 6.

The welding flash 7 has a substantially smaller dimension both in theradial and axial directions than that of the rib base portion 6. Moreparticularly, the welding flash 7 has less thickness than the rib baseportion 6. It has been found that the thickness of the welding flash 7relative to that of the rib base portion 6 should be between 1:10 and1:3, preferably about 1:5, to effectively avoid notch effects andcracking during welding.

The welding flash 7 may have equal dimensions along its full length ofcircumferential extent. By contrast, the rib base portion 6 of eachwelding rib 4, as is more particularly evident from FIG. 3, may consistof a pair of sections A, B diametrally opposed relative to the neckportion 1 of the weld component and tapering in a wedge-shape manneroutwardly in a radial plane. The sections A, B by their outercircumferences tangentially merge into the neck portion 1 and provide acontinuous notch effect minimizing transition of a film bag to beattached by welding when the weld component is inserted in a slot-shapedopening provided in the film bag.

A partition 5 located in the axial center plane, cf. FIG. 1, protrudesradially outwardly from diametral positions of the neck portion 1 andpasses centrally through the wedge-shaped sections A, B of each weldingrib 4. The partition 5 forms a supporting wall between adjacent weldingribs 4 having the effect that these retain the predetermined radial andaxial positions relative to the neck portion 1 when exposed to thestresses occuring during welding or in later use. Due to the stabilizingeffect of the partition 5 the thickness of the rib base portion 6 can bedimensioned for an optimum removal of heat from the welding zone whilstsimultaneously assuring a good supporting property for the film materialto be attached by welding. The partition 5 has preferably a smallthickness so that it reduces the exposed surface of the welding ribs 4only unsubstantially, thereby the heat transport via the welding ribs 4being affected practically not.

The face of the welding flash 7 forms a welding edge 8 extendingcircumferentially along the entire welding rib 4. While the outercircumferential surface of the base portion is preferably rounded, thewelding edge 8 of the welding flash 7 is preferably flat or tapersoutwardly.

In the embodiment of the invention as described above the partition 5ends in radial length from the neck portion 1 which is only slightlysmaller than that of the rib base portion 6 of each welding rib 4, cf.FIG. 1. If desired, the partition could also be extended radiallyoutwardly beyond the welding ribs 4 by a suitably short distance tosupport the film material to be attached by welding before it is spreadin the region of the welding ribs 4. Furthermore, the portion of thepartition protruding outwardly may have a lesser thickness than that ofthe portion located within the welding ribs.

A further embodiment of a plastic weld pourer component in accordancewith the invention is shown in FIGS. 4 to 6. This embodiment differsfrom that already described and shown in FIGS. 1 to 3 essentially inthat the weld component is split in an axial plane, preferably in theplane of the partition 5 of the embodiment as described above. Thiscreates two halves as shown in FIGS. 4 to 6 which may be mirror-inversein configuration.

Each half 10 comprises a neck portion 11 with a cross-sectionalconfiguration corresponding to that of the neck portion 1 of theembodiment described above when halved axially. Each half 10 contains acircumferentially closed through-passage 13 as well as a correspondingpart of the welding ribs 14 with rib base portions 16 and weldingflashes 17. Apart from being halved axially the welding ribs 14 may beconfigured the same as the welding ribs 4 of the embodiment as describedabove so that reference can be made hereto as regards further details.

Each half 10 is provided with congruent means, e.g. in the form ofpin/hole connections oriented towards each other, of which only the pins18 of one half are shown, for connecting the two halves to each otherreleasably by the pins 18 of one half being inserted in thecorresponding receiving holes (not shown) of the other half. When joinedtogether a configuration of the weld pourer component is formed whichcorresponds substantially to that as shown in FIGS. 1 to 3. Accordingly,a closure cap (not shown) can be screwed onto the thread 12 of the neckportions 11 when completed to close off both of the through-passages 13.

The embodiment of the invention as shown in FIGS. 4 to 6 enablesseparate container parts of a film material to be attached to each half10 by welding in the way as already described or to be secured theretoin some other way. After the halves 10 have been joined together thecontents of both container parts can be discharged via thethrough-passages 13 by exerting a force on the container parts, e.g. forbringing two components together for achieving a desired chemicalreaction, for mixing them or for applying them to a substrate at a time.

In welding the energy supplied causes the thin welding flashes 7 or 17to melt whilst the thicker rib base portion 6 or 16 of each welding rib4 or 14 substantially retains its rounded shape at the outercircumferential surface, so that the film material can abut thereto freefrom damaging notch effects as soon as the welding flash 7, 17 hasmelted away.

Above, the invention has been described on the basis of a weld pourercomponent having welding ribs 4, 14 extending radially to thelongitudinal center line of the neck portion. However, if desired, thewelding ribs could also be located at an angle to the longitudinalcenter line. Furthermore, if desired, the welding flash 7, 17 could bedivided circumferentially into sections, instead of extendingcontinuously along the circumference of each welding rib 4, 14. Furtheras regards further configurations of the weld pourer component, variousmodifications are possible which are obvious to a person skilled in theart due to the teaching given. For instance, the through-passage in theneck portion of the weld pourer component could be closed off by amolded cover having a pull tab to open it, instead of a screw orsnap-action cap. Also, a discharger element could be molded to the neckportion. A screw or snap-action cap could be formed integrally to theneck portion via a web or flange for closing off the through-passagehermetically during transporation and storage. After having parted theweb or flange the screw or snap-action cap may then be employed as usualto close the through-passage opened by the parting action.

I claim:
 1. A plastic weld pourer component for connecting to a plasticscontainer part made of film-like plastics material by welding,comprising:a tubular neck portion defining an elongated axialthrough-passage to serve as a discharge passage; at least one weldingrib formed as one piece with the neck portion and circumferentiallyextending thereabout, said welding rib including a thick-walled rib baseportion radially protruding outwardly from an outer surface of the neckportion and having a peripheral outer edge, and a thin-walled weldingflash formed as one piece with said rib base portion on the peripheralouter edge thereof and having a smaller radial dimension than that ofthe rib base portion; wherein a ratio of an axial dimension of thewelding flash relative to an axial dimension of the rib base portionimmediately adjacent the peripheral outer edge thereof is betweenapproximately 1:3 and 1:10.
 2. The weld pourer component as set forth inclaim 1, wherein a plurality of parallel welding ribs is providedaxially spaced from each other.
 3. The weld pourer component as setforth in claim 2, wherein a partition is formed to extend betweenadjacent welding ribs.
 4. The weld pourer component as set forth inclaim 1, wherein each welding rib has, as viewed from above, diametrallyopposed sections substantially wedge-shaped in configuration.
 5. Theweld pourer component as set forth in claim 1, wherein the outercircumferential edge of the rib base portion is rounded.
 6. The weldpourer component as set forth in claim 1, wherein the ratio of the axialdimension of the welding flash relative to the axial dimension of therib base portion at said peripheral outer edge is approximately 1:5. 7.The weld pourer component as set forth in claim 1, wherein the weldpourer component is divided into two parts along an axial plane in whicheach separate part comprises a discharge passage.
 8. The weld pourercomponent as set forth in claim 7, wherein the separate parts areconnectable to each other to complete the configuration of the neckportion to which a closure cap for sealing both discharge passages ofthe separate parts can be secured.
 9. A combination of a container partof film-like plastics material in the form of a refill bag, with a weldpourer component of dimensionally stable plastics materials, said weldpourer component comprising a tubular neck portion defining an elongatedaxial through-passage to serve as a discharge passage of said refillbag, at least one welding rib formed as one piece with the neck portionand circumferentially extending thereabout, said welding rib including athick-walled rib base portion radially protruding outwardly from anouter surface of the neck portion and having a peripheral outer edge,and a thin-walled welding flash formed as one piece with said rib baseportion on the peripheral outer edge and having a smaller radialdimension than that of the rib base portion, wherein a ratio of an axialdimension of the welding flash relative to an axial dimension of the ribbase portion immediately adjacent the peripheral outer edge thereof isbetween approximately 1:3 and 1:10.